Applies to audio or visual media manufacturing and recording tape or disc manufacturing.

Code 4431 applies to employers engaged in manufacturing removable recording or storage media used in audio or visual devices such as phonograph records, cassettes, videotapes, CDs, DVDs, and other recording media. 

Manufacturing phonograph records involves raw materials such as polymer, shellac, or vinyl which are ground and mixed, melted, and worked into a plastic consistency on hot rolls.  The resultant strips and sheets are then placed into heated record presses and compressed to form the records.  After the records have hardened and cooled, they are inspected, tested, labeled and packaged for shipment to the employer’s customers.

Cassettes and videotapes are manufactured through a process of polymerization in a clean-room environment.  The tape is coated with a ferromagnetic material and then wound in a protective plastic shell.  CDs and DVDs are manufactured from a polycarbonate material using an injection mold and vacuum evaporation process.  

Manufacturing or assembling audio or visual recording equipment such as tape recorders, video camcorders and projectors whether household or commercial type are assigned to Code 4923 “Photographic Supplies Mfg.”